Absorption refrigerating apparatus are known, some of which are provided with precoolers. The use of an evaporative precooler in a refrigerator is known to have certain thermodynamic advantages, however, these advantages are particularly evident under normal operating conditions of the apparatus. On the other hand, when the apparatus is cold when starting up difficulties arise with an apparatus having a precooler. Furthermore, if the apparatus works under varying conditions, disturbances may occur in the operation of the apparatus when the ambient temperature is high. However, if it is desired to overcome the above disadvantages and to supply a precooler of outstanding thermodynamic quality, the manufacture of a refrigerating apparatus will be complicated and the apparatus itself sensitive to varying operating conditions which may result in the disturbance of the precooling. This disturbance may occur especially when precooling is most needed.
It is a principal object of the present invention to provide an absorption refrigeration apparatus with a precooler in which the latter includes two parallel flow paths separated from but heat-conductively connected to one another, and means provided to raise the condensate in one of the flow paths to the gas conduit and to moisten the inner wall of the conduit with the condensate.
It is another object of the present invention to provide interior grooves in the precooler for providing a large moistened area of the pipe wall in the upper channel and a large contact surface for gas and liquid. Furthermore, the interior grooves also prevent the forming of liquid plugs in the precooler.
It is a further object of the present invention to provide a precooling device in which precooling takes place in two stages. The dimensions of the precooler are so chosen that the evaporation area is determined whereby it is possible to operate the apparatus with balanced temperatures of condensate and rich gas mixture before the latter leaves the precooler.